Lock seam eok pipe sections



June l2, 1928.

c. E. RUPPELT LOCK SEAM FOR PIPE SECTIONS Filed Jan. 50, 1928 Patented June 12, 1928.

PATENT OFFICE.

CLARENCE ERNEST RUPPELT, OF CANONSBURG, PENNSYLVANIA.

LOCK SEAM FOR PIPE SECTIONS.

Application filed January 30, 1928. Serial No. 250,689.

The ,present invention relates to lock seams,and as "here disclosed is shown' as applied to stove pipes, for which it is well adapted and more particularly intended, although it is to be understood that it is not limited to that specific use. i u

Its adaptability to rstovepipe s ectionslies in :the 4tact thatlby .its use a series ot pipe sections maybe nested together 'for .packing and transportation in unlocked condition, and when installed the sections Vmay be readily interlocked so Aas to give a secure fastening, and one which cannot ,be accidentally `unlocked either by straight pull or longitudinal shifting ot the .inteitloclied edges relative to each other.

VLock seams of 'the same general character as that herein disclosed are broadly old', but the lock seam which Ithave inventednhas certain advantages over the generally similar type nowknown to me, and my invention is directed to those improvements which are set tort-h and claimed `in the description which follows and are illustrated in the `drawings herewith which term a part of this disclosure.

In the drawings: i

[Figurel is a. view of a stove pipe section showing the seam, and in dotted `lines the location of the interlocking elements of the seam.

Figure' is an enlarged'view ottlie overlapping edges otra stove .pipe section showing the lock, this view being on the interior or the pipe. n I

"Figure 3 is a sectional view substantially on the line of Figure 2.

Figure 4 is a sectional view substantially on the line 4-4 of 'Figure 2.

Figure '5 is a view substantially on the line -ot Figure 2.

Figure 6 is a view of a'key for disassembling the section.

'Referring to the drawings by numerals, like numbers indicating like parts in the several views, 10 indicates a stove .pipe section lhaving interlocking edges 11 and 12.

The edge 11 ot' the-stove pipe section will he given a triple `told, asshown in Figures i5-and dat its extreme edge, two .of the 'plies at the Lpoint 13 being closely in contact to furnisha rigid and Vfinished outer seain sec tieni :while the third or free ply let will he et the interlocking pipe Y ,sectie` folded so as to give a groove or recess eX- tending longitudinally of the seam and designed to receive the opposite edge ot the pipe sectiontto lock the parts together. The ply 141 will be provided at intervals with openings 15, ypreferably o't rectangular shape as shown, and designed to receive and interlock with a complementary locking member formed on the opposite edge 12 of the pipe section.

The opposite edge 12 ot the stove pipe section is provided at intervals corresponding with the intervals between the opening 15 in the edge 11 with interlocking Aprojections 16 preferably, and as here shown, formed on the undersurtace ot lthe material, so that, when the seam is interloc'led and lthe section is ready tor use, the projections and interlocking elements will be on the inside ot thepipe and the exterior will .present a smooth, `linished, seam. 'The ,projection 16 is formed by dieing or stamping up a rectangular protuherance ot such dimensions as to lit snugly the opening 15, the parts 'beingproportioned so that while thei'loclring projection 16 will readily enter the opening 15 when the parts are brought to interlocking position, it will, nevertheless, be of such proportions as that it will prevent any shitting longitudinally et the two interloclred edges. rThe projection 16 is of sufficient height so as to give the abrupt ends 17 which, engaging the ends of the openings 15, will eliminate any relative endwise movement atter engagement of the parts.

The projection 1G will preferably be of `the form shown, that is, generally rounded throughout the greater portion of its area, "but at its inneredge it will be provided with 'a struck up locking member 18, this mem- `ber 18 being died out trom the edge ot the rounded Vproiection v16, and preferably, as

shown, to a point slightly beyond the .plane of the top -of the project-ion 16 so as to insure a lockingmember of suliicient'heiglit to securely engage `the edge of the opening 15 and hold the parts against disengagement by lateral movement. The yprojection l16 will be slightly inset from the edge 12 of the material, and the opening 15 ywillbe .set away from the bend 19 between. the ply 14 and the lplies 13 so-that the extreme edge 12 will engage the bottom of the recess when the locking projection 16 is brought to interlocking position relative to the opening l5 in the ply 14. This gives a securely nested, thoroughly rigid, construction, and eliminates any danger of buckling under strains imposed transversely of the seam.

The construction is one which not only gives a. very secure interlocking of the edges of the material, and one which cannot be dislodged either by lateral pull or by longitudinal shifting, since the parts are firmly interlocked against movement in either direction, but it also lends itself, by reason of its peculiar construction, to the ready assembling of the edges. The extreme flat edge 12 of the pipe may be very readily entered in the recess between the ply 14 and the plies 13 with the projection 16 and the openings 15 registering, and then by applying pressure to the pipe the rounded projection 16 will readily slide into place, the relatively thin flexible section 2O of the ply 14 will snap over the locking member 18, and the parts securely interlocked and in rigidly nested condition, as shown best in Figures 3 and 4.

Furthermore, the construction is one which involves only simple manufacturing problems. A sheet of stock of proper dimensions may be taken in flat condition, one edge subjected to the action of dies to stamp up the interlocking projections, and this may be readily done by one dieing operation, while the opposite edge may be punched to form the lock receiving openings and then folded to give the double stifTening plies and the receiving recess for the opposite edge. I regard itl as of considerable importance that the locking projection is inset from the edge o1" the material so as to leave a Hat groove engaging portion, and that. the receiving recess between plies 13 `and the ply 14 extends some distance beyond the opening 15 to receive this extended edge, for this gives a very complete and rigid seam and eliminates any possibility of the inserted edge 12 from rocking or shifting in the opening and gives a rigidity to the seam, which. Without this nesting of the extreme edge of the section 12 in the bottom of the recess, would not be secured.

In Figure 6, the key is shown for unlocking the joint. Itf comprises a rounded .shank portion 22 and a flattened head portion 23. The length of the head portion is the same as the Width of the thin flexible section 20. This insures against any possibility of the key head extending into and catching in the locking member 18.

By placing the flat key head beneath the section 20 with the shank portion 22 at right angles thereto, a forcing of the shank portion to a parallel position with and against the stove pipe Will lift the section 20 Suthciently to allow the locked member 18 to be easily Withdrawn from the opening 15.

In Figure 4, the dotted lines show the section 20 lifted in order that the locking meinber may be Withdrawn. The key is also shown in dotted lines in Figure 2.

This unlocking feature facilitates disassembling the sectional stove pipes, and eliminates the prevailing danger of injury to the locking members, as is the case when any sharp pointed tool is used to pry them open.

Obviously, changes in the make-up of the seam may be made Without departing from the range of my invention or from the scope of the claims in which I have specified that Which is new.

1. A lock seam of the character described` comprising a recessed member a wall of which is provided with an interlocking opening, a recess engaging member, and an interlocking projection on said last-named member the ends of which engage the ends of the interlocking opening to prevent relative longitudinal movement of said members, and interlocking means on said projection to prevent relative lateral movement of said members.

2. A lock seam of the character described, comprising a recessed member a Wall of which is provided with an interlocking opening, a recess engaging member, an interlocking projection having a curved upper surface and substantially vertical ends to engage the end walls of the opening and lock said members against relative longitudinal movement, and a projection extending laterally from said first-named projcction between its ends to engage a side wall of said opening and prevent relative lateral movements ot said members.

3. A lockseam of the character described` comprising a .recessed member a wall of which is provided with an interlocking opening, a recess engaging member, a substantially half-round interlocking projection having substantially vertical ends on said last-named member to engage the opening and lock .said members against relative longitudinal movement, and a second projection extending laterally from said trstnamed projection between its ends and having a substantially vertical face to engage said opening and lock said members against relative lateral movement., said last-named projection extending above the plane of the top of said first-named projection.

4. In a lock seam construction, an interlocking member having a series of integral rounded projections struck from the material thereof and provided with substantially vertical ends, and a second locking projection struck from the first-named projection between and at right angles to its ends.

5. In a lock sen-n1 construction, an inter- Second projection extending above the pla-ne locking member having a series of integral of the top of said first-named projection and rounded projections struck from the inatehaving a substantially vertical end. l0 rial thereof and provided with Substantially In testimony whereof I have hereunto set a vertica ends7 and e second looking projecmy hand.

tion Struck from the rstmamed projection between and at right angles to its ends, said CLARENCE E. RUPPELT. 

